Correlating otopathological analysis with genetic screening for existing syndromic and non-syndromic inner ear diseases is the goal of the House Ear Institute's contribution to the NIDCD's Otopathology Research Collaboration Network. The value of these correlations lies in connecting genetic diagnosis with a better understanding of disease progression and pathological sequelae, as well as the identification of targets for future treatment and, importantly, improved genetic counseling. Because of an almost complete lack of human biopsy material associated with inner ear disease, such connections remain largely unknown, and the only source of this information is the existing post-mortem temporal bone collections. For this reason, we have developed techniques for extracting and analyzing biological material (DNA and protein) from existing archival temporal bones for which relevant clinical data is cataloged and available. Here, we propose several Specific Aims designed to identify the underlying genetic mutations/genetic variants in existing temporal bone collections housed by members of our consortium, with the purpose of establishing a genotype/otopathology phenotype correlation. This has not been done consistently for any of the known genetic disorders of the inner ear, and the successful outcome of this proposal promises to provide an enhanced resource for the clinician and researcher who wish to link the etiology of inner ear disease with its otopathological outcome. PUBLIC HEALTH RELEVANCE: Molecular biological techniques have only recently been applied to study the correlation of biological structure with function in normal and diseased human temporal bones. This proposal will fill the knowledge gap by performing a comprehensive genotype-phenotype correlation in four hearing disorders;1) Hereditary, 2) Meniere's, 3) Otosclerosis, and 4) NF2.